Ion implantation is a technique for introducing property-altering impurities into substrates. During a typical ion implantation process, a desired impurity material is ionized in an ion source, the ions are accelerated to form an ion beam of prescribed energy, and the ion beam is directed at the surface of a substrate. The energetic ions in the ion beam penetrate into the sub-surface of the substrate material and are embedded into the crystalline lattice of the substrate material to form a region of desired conductivity or material property.
An ion implanter may generate an ion beam having a roughly circular or elliptical cross sectional shape that is smaller than the surface of a substrate to be treated. A substrate, which may be a semiconductor, for example, may have a round, disk shape. In order to implant ions into substantially the entire surface of the substrate, the substrate may be mechanically driven or “scanned” in a direction that is orthogonal to the direction of an ion beam projected thereon. For example, if an ion beam is projected along a horizontal plane toward a vertically-oriented substrate, the substrate may be scanned in a vertical direction and/or in a lateral direction that is perpendicular to the projected ion beam. The entire surface of the substrate may thereby be exposed to the relatively smaller ion beam during an implantation process.
In order to mitigate particulate contamination of substrates during ion implantation processes, ion implantation apparatuses often include robots located within vacuum environments for supporting and scanning substrates. Such robots are generically referred to as “vacuum robots.” A vacuum robot may include a controllably movable platen to which a substrate may be clamped. For example, the platen may be slidably mounted on a pair of vertically-oriented shafts and may be coupled to a linear drive mechanism that may be adapted to controllably drive the platen to various vertical positions along the shafts. The platen may be coupled to the shafts by differentially pumped air bearings that prevent or reduce physical contact between the shafts and the platen, thereby mitigating the production of particle contaminants that could otherwise be produced as a result of such contact.
Vacuum robots of the type described above can include numerous components that must be coupled to respective facilities by coupling members for supporting various functions, such as providing power and control signals to motors, providing pressurized gas and vacuum pumping for air bearings, providing cryogenic fluid for cooling the platen, etc. All such coupling members must be sealed from the process environment to prevent contamination of the substrates. Furthermore, cryogenic lines, if routed in a region of atmospheric gas, must be heavily insulated to prevent condensation and ice from forming on the outer surfaces thereof.
Coupling members can be routed through the interiors of vacuum robots to their respective components. Larger coupling members, such as heavily insulated cryogenic lines, are often routed through harnesses that are externally attached to the vacuum robot. Such routing schemes are associated with a number of shortcomings. For example, they consume a great deal of space within a process environment, they limit the mobility of vacuum robots, and they typically produce an appreciable amount of particle contamination. Thus, it would be advantageous to provide a solution for routing cryogenic lines and the like to vacuum robots and other components within vacuum environment in a manner that reduces the amount of space such lines occupy, that enables greater robot mobility, and that minimizes or eliminates the generation of particulate contamination within the vacuum environment.